Merge pull request #1190 from DataDog/devinsba/hibernate-null-entity-check

Add null check to hibernate decorator

dd-java-agent/instrumentation/hibernate/src/main/java/datadog/trace/instrumentation/hibernate/HibernateDecorator.java

@@ -47,6 +47,9 @@ public class HibernateDecorator extends OrmClientDecorator {
 
   @Override
   public String entityName(final Object entity) {
+    if (entity == null) {
+      return null;
+    }
     String name = null;
     final Set<String> annotations = new HashSet<>();
     for (final Annotation annotation : entity.getClass().getDeclaredAnnotations()) {